U.S. patent number 4,756,176 [Application Number 06/873,811] was granted by the patent office on 1988-07-12 for fence lever control device for a combination lock.
This patent grant is currently assigned to La Gard, Inc.. Invention is credited to Tim M. Uyeda.
United States Patent |
4,756,176 |
Uyeda |
July 12, 1988 |
Fence lever control device for a combination lock
Abstract
A fence lever control device for a combination lock provides a
pivoted plate having an arm positioning a spring to normally bias
the fence lever of the lock in a position out of engagement with
the fence lever operating cam wheel, with an actuator roller
mounted to the cam wheel which engages a follower surface on the
pivoted plate once on each complete revolution of the cam wheel in
a given direction in response to similar rotation of the dial shaft
to which the cam wheel is mounted to thereby shift the pivoted
plate and its associated spring mounting arm in an over center
fashion to place the spring in a position to bias the fence lever
toward the cam wheel, movement of the fence lever into engagement
with the cam wheel being prevented by engagement between the fence
member and the tumbler wheel assemblies when the wheel assemblies
are not oriented in a predetermined relationship.
Inventors: |
Uyeda; Tim M. (South San
Gabriel, CA) |
Assignee: |
La Gard, Inc. (Torrance,
CA)
|
Family
ID: |
27101589 |
Appl.
No.: |
06/873,811 |
Filed: |
June 13, 1986 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
676628 |
Nov 30, 1985 |
|
|
|
|
Current U.S.
Class: |
70/303A; 70/301;
70/315; 70/321 |
Current CPC
Class: |
E05B
37/08 (20130101); Y10T 70/7254 (20150401); Y10T
70/7237 (20150401); Y10T 70/7322 (20150401); Y10T
70/7356 (20150401) |
Current International
Class: |
E05B
37/08 (20060101); E05B 37/00 (20060101); E05B
037/08 () |
Field of
Search: |
;70/302,33A,33R,316,301,321,322,315,317,318 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
159448 |
|
Oct 1954 |
|
AU |
|
644382 |
|
Jul 1962 |
|
CA |
|
Primary Examiner: Wolfe; Robert L.
Assistant Examiner: Dino; Suzanne L.
Attorney, Agent or Firm: Poms, Smith, Lande & Rose
Parent Case Text
This application is a continuation of Ser. No. 676,628, filed
11/30/85 and now abandoned.
Claims
I claim:
1. An improved fence lever control device for impeding unauthorized
opening of a combination lock through manipulation of the lock
components wherein said lock includes a housing, a bolt slidably
mounted to the housing, a fence lever moveable about a pivot for
operating said bolt relative said housing, a fence member on said
lever, a lock dial shaft rotatably mounted to said housing, a
plurality of gated wheel assemblies rotatable within said lock
housing by rotation of said dial shaft with alignable gates in said
assemblies to align with said fence member when said assemblies are
oriented in a predetermined manner, a cam wheel on said dial shaft
having a cam gate in said wheel, and a nose portion of said fence
lever which can enter said cam wheel gate when said assembly gates
are aligned to said fence member and said fence lever nose is
aligned to said cam gate to thereby move said bolt by operation of
said fence lever, said device comprising:
a spring connected at a spring first end to said fence lever;
a plate pivotally mounted to said housing at one end of said plate
and having an extension arm integral with said plate, said
extension arm acting as an over center lever and being connected to
a second end of said spring;
said plate, extension arm and spring being provided so as to
normally place said spring second end above a centerline drawn
through a point on said fence lever where said first spring end is
connected to said fence lever and the center of the pivot for said
fence lever to normally bias said fence lever nose portion away
from said cam gate;
means for pivoting said plate and extension arm once, during a full
revolution of said dial shaft sufficiently to place said spring
second end below said center line so as to bias said fence lever by
said spring in a direction toward said gated wheel assemblies and
cam wheel to allow lock opening operation thereof if the
combination of said lock has been entered to place said gated wheel
assemblies in a gate aligned relation to said fence member.
2. An improved fence lever control device for a combination lock
having a fence lever pivotally mounted to pivot about a pivot axis
for operating an associated bolt, a plurality of gate wheels
rotatable into a gate aligned relationship relative to the fence
lever on rotation of an associated dial shaft in accordance with a
predetermined combination of dial rotation, a cam wheel with a cam
gate for engaging the fence lever to move it and shift the bolt to
an unlocked position when the fence lever engages the cam wheel
gate allowed when the gate wheels are in said aligned orientation,
said fence lever control device comprising:
a spring connected at one end to said fence lever;
an over center lever connected to a second end of said spring and
mounted for shifting movement between a first position wherein said
lever positions said spring second end above a centerline drawn
through a point on said fence lever where said spring one end is
connected to said fence lever and the pivot axis of said fence
lever to bias said fence lever away from said wheel assemblies and
cam wheel and a second position wherein said lever positions said
spring second end below said centerline to bias said fence lever
toward said wheel assemblies and cam wheel; and
actuator means driven by shaft rotation for shifting said over
center lever from its first position to its second position once
each shaft rotation.
3. The fence lever control device of claim 2 wherein said device
further comprises:
stop means for limiting shifting movement of said over center lever
in the direction of shifting movement into said first position.
4. The fence lever control device of claim 2 wherein said fence
lever control further comprises:
follower surface means on said over center lever to cause said over
center lever to follow said actuator means and said actuator means
includes a cam roller mounted to said cam wheel to shift said over
center lever by engagement with said follower surface means from
said first position to said second position.
5. The fence lever control device of claim 2 wherein said lock
includes a housing and wherein said control device further
comprises:
a plate pivotally mounted by a pivot pin to said housing at one end
thereof, a cam follower surface formed therein for engagement with
a cam roller, an extension arm and a spring end mounting flange at
a free end of said arm spaced further away from said pivot pin than
the spacing therefrom of said follower surface;
a cam roller mounted to said cam wheel; and
said over center lever and cam roller being provided for engagement
of said follower surface by said roller on each revolution of said
cam wheel in a given direction to shift said over center lever
toward its second position.
6. In a combination lock having a housing, a lock dial shaft, a
bolt operated by a fence lever turnable about a pivot axis and
mounting a fence lever nose, a plurality of tumbler wheels mounted
on and rotatable by said shaft, a fence lever receiving gate in
each of said wheels, a cam wheel and a cam gate for receiving said
nose, rotation of said cam wheel when said nose is in said cam gate
operating said lever to move the associated bolt, said engagement
being allowed only when said wheel gates are aligned to one another
and receive said fence,
fence lever control and means for normally keeping said nose spaced
from said cam wheel and for moving said nose toward said cam wheel
in a predetermined manner in response to rotation of said cam wheel
whereby premature, lock manipulation type contact between said nose
and cam wheel gate are prevented until said time as said tumbler
wheel gates are aligned to receive said fence as a prerequisite to
nose engagement with said cam wheel, the improvement in said fence
lever control means comprising the provision of:
a spring connected at one end to said fence lever;
a plate pivotally mounted to said housing about a fixed pivot at
one end of said plate, a cam follower surface formed therein for
engagement with a cam roller, an extension arm integral with said
plate and being provided for a pivoting movement about said fixed
pivot between said fence lever and said lock dial shaft, said
extension arm acting as an over center lever and having a spring
end mounting flange at a free end thereof, said spring end mounting
flange being spaced further away from where said plate is pivotally
mounted to said housing than from said follower surface;
said extension arm having its spring end mounting flange connected
to a second end of said spring and being mounted for shifting
movement between a first position wherein said extension arm
positions said spring second end above a centerline drawn through a
point where said said spring one end is connected to said fence
lever and said pivot axis of said fence lever so as to normally
bias said fence lever away from said tumbler wheels and said cam
wheel and a second position wherein said extension arm positions
said spring second end below said centerline to bias said fence
lever toward said tumbler wheels and said cam wheel; and
a cam roller mounted to said cam wheel, said extension arm and cam
roller being provided for engagement of said follower surface by
said roller on each revolution of said cam wheel to shift said
extension arm toward its second position.
Description
BACKGROUND OF THE INVENTION
This invention relates in general to combination locks and in
particular to an improved fence lever control device for normally
maintaining the fence lever out of engagement with the cam wheel of
the lock which is utilized for operating the lever to move the lock
bolt between lock open and lock closed positions.
It is common in combination locks, such as that disclosed in the
U.S. Pat. No. 4,142,388, for the nose portion of the combination
lock fence lever to ride normally on the outer periphery of the cam
wheel so that the fence member associated with the fence lever will
not ride upon the tumbler wheels of the lock mechanism. Otherwise,
an unauthorized, but lock manipulation skilled person, might
endeavor to manipulate the lock mechanism and "feel" the engagement
between the fence member and the wheel assembly gates to thereby
determine the combination for the lock. However, it has also been
found that the engagement between the nose portion of the fence
lever and the gate of the cam wheel, by which the fence lever is
engaged and operated to move the bolt to an open position by
rotation of the cam member, can allow for an unauthorized lock
manipulation skilled person to determine where the cam wheel gate
is and then by manipulating the lock parts in a predetermined
manner also bring the fence member in contact with edges of the
gates of the wheel assemblies while the lever nose is positioned in
the cam wheel gate.
In order to overcome the contact or "feel" of the fence lever with
the rotating lock portions inclusive of the cam wheel and gate
wheel assemblies, means have been developed heretofore such as in
U.S. Pat. No. 3,991,596, for normally maintaining the fence lever
in an inactive position out of engagement with the rotating lock
parts. However, it is believed that these prior mechanisms have
been fairly complicated in their assembly operations, are not
easily added, or adapted to ease of assembly techniques, in mass
production of combination locks and generally required some
manipulation of the combination of the lock to release the lever in
a manner which may or may not be always reliable to cause opening
of the lock.
SUMMARY OF THE INVENTION
It is, therefore, the primary object of the present invention to
disclose and provide a simple yet reliable and effective
construction and mode of operation for a fence lever control device
to normally hold the fence lever in an inoperative position and yet
is operated with each revolution of the dial shaft without
effecting other operating conditions or parts of the lock
mechanism. It is a further object of the present invention to
provide such a device that can be easily assembled to a combination
lock during the assembly techniques and which requires relatively
few parts operating in a simple and inexpensive manner to produce a
reliable and repeating motion of the device which will not give an
unauthorized lock manipulating person any "feel" for opening the
lock through movement and/or engagement between the fence lever and
the gate wheel assemblies and/or cam wheel.
Generally stated, the present invention in a fence lever control
device for a combination lock includes the provision of means for
normally keeping the nose of the fence lever spaced from the cam
wheel, such means being so provided so as to move the fence lever
and its associated nose toward the cam wheel in a predetermined
manner correlated to, and operating in response to, rotation of the
dial shaft in a predetermined manner whereby premature, lock
manipulation type contact between the fence wheel nose and the cam
wheel gate are prevented until such time as the tumbler wheel gates
are aligned to one another and are ready to receive the fence
member of the fence lever as part of the authorized opening of the
lock by dialing a predetermined lock combination.
More specifically, the present invention in a fence lever control
device includes the provision of a biasing means for normally
biasing the lever to its inactive position and for once, during
each revolution of the dial shaft in a given direction, biasing the
lever toward the cam wheel and gate wheel assemblies during a
portion only of such revolution. In a preferred exemplary
embodiment of the present invention, such biasing means includes a
spring connected at one end to the fence lever, an over center
acting arm connected to a second end of the spring and mounted for
shifting movement between an first position where the arm positions
the spring to bias the fence lever away from the cam wheel and
wheel assemblies and a second position wherein the arm positions
the spring to bias the fence lever toward said assemblies and cam
wheel, and actuator means driven by dial shaft rotation in a given
direction for shifting the over center arm from its first position
to its second position once during each shaft revolution in a given
direction. On such shifting movement of the over center arm by the
actuator means during each shaft revolution as stated, if the wheel
assembly gates are aligned, the fence lever is allowed to move its
nose into engagement with the cam wheel gate since the fence member
of the fence lever will enter such wheel gates. However, if the
combination has not been correctly entered and the gate wheel
assemblies are not aligned to receive the fence member, the fence
member will be held up by engagement with the outer peripheries of
the wheel assemblies as the cam wheel gate passes beneath the nose
of the fence lever and the spring connected between the fence lever
and the over center arm will shift the over center arm away from
its second position back into its first position.
It is believed that a more complete understanding of the
improvement in the fence lever control device of the present
invention will be afforded to those skilled in the art from a
consideration of the following detailed description of a preferred
exemplary embodiment thereof. Reference will be made to the
appended sheets of drawings which will first be described
briefly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view, partially in section to remove the cover,
of an exemplary combination lock having a preferred exemplary
embodiment of fence lever control device in accordance with the
present invention.
FIG. 2 is a section view of the lock of FIG. 1 taken therein along
the plane II--II.
FIG. 3 is a front view of the lock of FIG. 1 showing the preferred
exemplary embodiment of fence lever control device holding the
fence lever free of the cam wheel of the lock.
FIG. 4 is a front view of the lock of FIG. 1 showing the exemplary
embodiment of fence lever control device moving the exemplary fence
lever into engagement with the gate of the cam wheel.
FIG. 5 is a partial section view of the lock of FIG. 3 taken
therein along the plane V--V.
FIG. 6 is a detail section view of a portion of the exemplary fence
lever control device taken in the plane VI--VI of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EXEMPLARY EMBODIMENT
Referring initially to FIGS. 1 and 2, an exemplary embodiment of
the combination lock is illustrated as an exemplary embodiment of
lock mechanism in which the present invention in an improved
control device for operating the fence lever is illustrated. The
exemplary lock includes a housing 10 mounted on the interior of a
safe door 11 with an interdisposed guard plate 12 by appropriate
mounting screws 13 in known fashion. The guard plate and lock
mounting means may be provided as in the disclosure of U.S. patent
application Ser. No. 508,119 filed June 27, 1983 entitled
"Protective Lock Mounting Plate For Safe Door Locks" or
alternatively as disclosed in application for U.S. patent
application Ser. No. 649,666 filed Sept. 12, 1984 entitled "Lock
Protecting Device For High Security Safes.". The exemplary lock
includes a bolt 14 which is adapted to be received within a
receptacle 15 formed in the safe wall in conventional manner. The
generally box configuration housing 10 is provided with a cover 17
which is held in place by mounting screws 18.
Exemplary of the types of combination locks in which the present
improvement in a fence lever control device finds use are the locks
illustrated in the prior U.S. Pat. No. 4,142,388 entitled "Tumbler
Wheels For Combination Locks" and in the disclosure of application
for U.S. Letters Patent Ser. No. 289,452 filed Aug. 3, 1981
entitled "Combination Lock", the disclosures of which are
incorporated herein by reference. However, for purposes of the
present disclosure, it is noted that locks of this general type
employ a fence lever 20 which is pivotally mounted at one end by a
pivot screw 21 secured to bolt 14 and have a fence 22 protruding
laterally from an opposite free end which is adapted to cooperate
in known manner with the gates 23a, 24a and 25a, respectively, of
the exemplary gate wheel assemblies 23, 24 and 25. The gate wheel
assemblies are generally formed with an inner drive ring
manipulated by rotation of dial shaft 19 and have an outer
relatively adjustable gate ring as more fully disclosed in said
U.S. Pat. No. 4,142,388 and said application for U.S. patent
application Ser. No. 289,452.
As is further customary in combination locks, a cam wheel 26 is
provided on an inner end of the dial shaft 19 and is provided with
a cam gate 27 to cooperate with a nose 29 formed on the lower
portion of the free end of fence lever 20 as best seen in FIGS. 1,
3 and 4. When the fence lever nose 29 is in engagement with the cam
gate 27, allowed only when the combination has been correctly
dialed and the fence 22 is received in the tumbler wheel assembly
gates aforedescribed, further manipulation of the dial shaft as by
turning the dial in the correct direction will pull bolt 14 out of
the safe wall receptable 15 to cause unlocking of the combination
lock. It has been known heretofore that unauthorized entry into
combination locks can be achieved by persons very skilled in the
lock manipulation art by turning the lock dial and its associated
shaft to hopefully bring portions of the tumbler wheels, and
particularly their gates, in contact with the fence and thus it is
common to have the fence lever nose 29 normally ride on the
exterior surface or periphery 28 of cam wheel 26. However, it has
also been found that persons skilled in the lock manipulation art
can use even slight indications or "feel" imparted to the dial by
the fence lever nose 29 engaging lateral extremities of the cam
wheel gate 27 in a lock manipulation procedure. Attempts have,
therefore, been made heretofore, as in U.S. Pat. No. 3,991,596
entitled "Tumbler Wheel, Changeable Combination T-Lock
Construction" to maintain portions of the fence lever 20 free of
the tumbler wheel assemblies and cam wheel until such time as the
correct combination is dialed for the lock. In the disclosure of
Patent '596, the pivoted fence lever is normally held out of
engagement with the tumbler wheel assemblies and cam wheel by a
releasable latch mechanism in an inactive position. As a part of
correctly operating the combination lock with the authorized
combination, associated cam members and spring devices are operated
to impact upon the fence lever and throw it toward the tumbler
wheel assemblies. As stated hereinbefore, it is a primary object of
the present invention to disclose a more simplified, inexpensive
and independently operating device for controlling movement of the
fence lever which is not dependent upon other portions of the lock
mechanism or the dialing of the correct combination.
As is particularly contemplated within the present invention, an
improved fence lever control device is indicated generally at 30 in
the drawings of the within disclosure for normally biasing the
fence lever 20 and its fence member 22 and nose 29 away from the
gate wheel assemblies 23, 24 and 25 and away from the cam wheel 26,
respectively, which is operable to bias the fence lever toward the
gate wheel assemblies and cam wheel once during each rotation of
the dial shaft during only a portion of the shaft revolution in
such a manner that if the combination has been dialed correctly
during such revolution, the lock can be opened. In the preferred
exemplary embodiment, such control device includes a plate 31
mounted at its left hand end in FIGS. 1, 3 and 4 by a pivot pin 32
to the mounting boss 33 formed integrally of lock housing 10. Plate
31 has a laterally extending arm 34 which extends to the right in
FIGS. 1, 3 and 4 past the upper free end of the fence lever 20
where an upstanding flange 35 formed integrally of arm 34 mounts a
spring 36 secured thereto via aperture 37. Spring 36 is connected
at an opposite end to the free end of fence lever 20 by the tab 38
as best seen in FIGS. 2 and 5, there being an aperture, as seen in
FIG. 5, in the tab for receiving the spring end. A stop portion 40
is formed in plate 31 in a portion directly upwardly of the
mounting at pivot pin 32 to hold the plates counterclockwise
revolution to the position illustrated in FIGS. 1 and 3 wherein the
control device arm 34 and associated flange 35 mount spring 36 in a
position wherein the tension of spring 36, in attempting to pull
the lever free end at tab 38 toward flange 35, holds the fence
lever 20 in the raised inactive position of FIGS. 1 and 3.
As is further particularly contemplated within the present
invention, the fence lever control device of the present invention
includes actuator means driven by shaft rotation for shifting the
plate 31 and its associated arm 34 (acting as an over center lever)
to an over center, active fence lever biasing position wherein
spring 36 biases the fence lever 20 toward the gate wheel
assemblies 23, 24 and 25 and the fence lever nose 29 toward the cam
wheel gate 27 as seen in FIG. 4. Such actuator means in the
exemplary embodiment includes an actuator roller 41 rotatably
mounted by shaft 42 on the cam wheel 26 so that it revolves with
rotation of the dial shaft 19.
The combination for the lock may be predetermined as in the
combination locks of said U.S. Pat. No. 4,142,388 and U.S. patent
application Ser. No. 289,452 actuator roller 41 engages the lower
portion 44 of plate 31 when being rotated in either direction. When
roller 41 is in the position of FIG. 3, it to engages the upper
follower surface 43 of lower portion 44 in a manner to pivot plate
31 into its over center, active position of FIG. 4 wherein spring
36 biases gate lever 20 into engagement with the gate 27 of cam
wheel 26, such event occurring only if the correct combination has
been dialed so that the gates 23a, 24a and 25a are aligned with
fence 22. Rotations of the dial in clockwise directions during
operation of the combination will similarly pivot plate 31 into its
over center position.
It should be apparent from the foregoing disclosure, that on
rotation of the lock dial shaft 19 in either rotational direction
as viewed in FIGS. 3 and 4, the actuator wheel 41 will pivot the
fence lever control device plate 31 toward the position of FIG. 4
once on every revolution of the dial shaft, as for example, in the
counterclockwise direction indicated by the arrow in FIG. 4 whether
the correct combination has been dialed or not. If the correct
combination has not been dialed, then the fence 22 will engage the
outer periphery of the gate wheel assemblies 23, 24 and 25 holding
the fence lever 20 in a raised, intermediate position between the
positions illustrated in FIGS. 3 and 4 wherein the lever nose 29
will not enter the cam wheel gate 27. As soon as the actuator
roller 41 releases the cam plate 31 by leaving the follower surface
43, as illustrated in FIG. 4, but assuming that the fence 22 is
riding on the nongate aligned wheel assemblies 23, 24 and 25, the
tension of spring 36 will return the plate 31 and its associated
arm 34 in a counterclockwise direction to the inactive position of
FIG. 3 with such counterclockwise movement being limited by the
stop 40 engaging a side wall of housing 10. The fence lever 20 is
thus maintained biased in its inactive or raised position out of
engagement with the tumbler wheels and cam wheel thereafter until
the dial shaft is rotated in a further full counterclockwise
rotation to once again bring the actuator roller 41 into engagement
with the follower surface 43.
As is now apparent to those skilled in the art, the fence lever
control device of the present invention is very simple in its
construction and mode of operation, the plate 31 and spring 36
being so provided as to be mounted at the end of a lock assembly
procedure after the tumbler wheel assemblies, fence lever and bolt
mechanism have all been assembled into the lock housing. Plate 31
is a simple stamped and formed member and is operated on each full
revolution of the lock dial shaft by roller 41 to provide a
consistent sound and "feel" to the lock operation unrelated to a
correct dialing of the combination and without the need for complex
devices or parts for normally holding the fence lever 20 in an
inactive position out of engagement with the gate wheel assemblies
and cam wheel. Having thus described a preferred exemplary
embodiment of the fence lever control device of the present
invention, it should be noted by those skilled in the art that
various modifications, adaptations and equivalent embodiments may
be made within the spirit and scope of the present invention which
is defined by the following claims.
* * * * *